초록 |
Morphological characteristics and formation of symmetric polystyrene-block-poly(1,4-butadiene) copolymer (PS-b-PBD) in thin films upon solvent-annealing were investigated by using atomic force microscopy (AFM). The thin films solvent-annealed in cyclohexane revealed the perforated lamellae of poly(1,4-butadiene) in the matrix of polystyrene while those solvent-annealed in n-hexane exhibited highly disordered patterns. Interestingly, when the thin films of PS-b-PBD were solvent-annealed with binary mixtures of cyclohexane and n-hexane, the morphological transition from the perforated lameallae to the perpendicularly-oriented lamellae of poly(1,4-butadiene) could be induced by changing the mixing ratio of both solvents. We also demonstrated that after microdomians of poly(1,4-butadiene) were successfully degraded by UV-O3, linear poly(dimethyl siloxane) chains were back-filled into the etched regions of the thin film and then converted to silica nano-objects by oxygen plasma treatments. |